The last few years have seen the appearance of a number of drugs sold under the false flag of "bath salts" or "plant food". Generally mephedrone and methylone, their abuse has lead to a number of hospitalizations in the last year. And that's led to increased pressure to understand how they work, and just how safe they really are.

The differences start to appear in high doses. All three drugs induce hyperthermia, but it's far more severe with MDMA. Even more interestingly, MDMA is linked to long-term depletion of serotonin, which the designer drugs aren't. While this is all in rat models, it does appear that in some instances these new "legal highs" might be safer than the traditional ones.